ABSTRACT
Aristotle first claimed that the essence of justice was that equals should be treated equally and unequals unequally (Aristotle 1958). That seemingly innocuous formal phrase can be taken apart in any number of ways, but in general it can be understood as claiming that justice requires that in so far as agents are the same in morally relevant respects then they should be treated the same, and in so far as they differ in those respects they should be treated differently (Feinberg 1980, Westen 1990, Raz 1986: 217-44). In the liberal paradigm we are assuming here, it is claimed that all human beings are equal in their basic moral status, that they equally deserve respect as autonomous beings. But this leaves open the question of what treatment such equal status requires, what ways such beings are ‘the same’ so that, following Aristotle’s dictum, they should be treated the same. This shows how the
crux of arguments about equality is the phrase ‘morally relevant respects.’ Disagreements over how much, and in what ways, equality should be promoted in a society will turn on arguments about what are the relevant respects in which people are all the same.
